Decoherence-assisted transport and quantum criticalities

TL;DR

This paper investigates how a quantum environment influences a two-level system's dynamics, revealing that environmental phase transitions significantly affect noise-assisted transport phenomena.

Contribution

It demonstrates the sensitivity of noise-assisted quantum transport to environmental quantum criticalities, linking transition probabilities to phase changes in the environment.

Findings

Transition probability peaks at environmental critical points.

Noise-assisted transport is enhanced near quantum phase transitions.

Environmental phase changes impact quantum system dynamics.

Abstract

We study the dynamics of a two-level quantum system interacting with an external environment that takes the form of an XY spin chain in the presence of an external magnetic field. While the presence of the bath itself can enhance the transition probability from the lower level to the upper level of the system, we show that this noise-assisted phenomenon is sensitive to a change of the quantum phase of the environment. The derivative of the transition probability displays a maximum in correspondence with the critical value of the applied field both in the case of isotropic and anisotropic chains.